linux/fs/xfs/xfs_extfree_item.c
Christoph Hellwig 272e42b215 xfs: constify xfs_item_ops
The log item ops aren't nessecarily the biggest exploit vector, but marking
them const is easy enough.  Also remove the unused xfs_item_ops_t typedef
while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
2011-11-08 10:48:23 -06:00

521 lines
14 KiB
C

/*
* Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_trans_priv.h"
#include "xfs_extfree_item.h"
kmem_zone_t *xfs_efi_zone;
kmem_zone_t *xfs_efd_zone;
static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_efi_log_item, efi_item);
}
void
xfs_efi_item_free(
struct xfs_efi_log_item *efip)
{
if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
kmem_free(efip);
else
kmem_zone_free(xfs_efi_zone, efip);
}
/*
* Freeing the efi requires that we remove it from the AIL if it has already
* been placed there. However, the EFI may not yet have been placed in the AIL
* when called by xfs_efi_release() from EFD processing due to the ordering of
* committed vs unpin operations in bulk insert operations. Hence the
* test_and_clear_bit(XFS_EFI_COMMITTED) to ensure only the last caller frees
* the EFI.
*/
STATIC void
__xfs_efi_release(
struct xfs_efi_log_item *efip)
{
struct xfs_ail *ailp = efip->efi_item.li_ailp;
if (!test_and_clear_bit(XFS_EFI_COMMITTED, &efip->efi_flags)) {
spin_lock(&ailp->xa_lock);
/* xfs_trans_ail_delete() drops the AIL lock. */
xfs_trans_ail_delete(ailp, &efip->efi_item);
xfs_efi_item_free(efip);
}
}
/*
* This returns the number of iovecs needed to log the given efi item.
* We only need 1 iovec for an efi item. It just logs the efi_log_format
* structure.
*/
STATIC uint
xfs_efi_item_size(
struct xfs_log_item *lip)
{
return 1;
}
/*
* This is called to fill in the vector of log iovecs for the
* given efi log item. We use only 1 iovec, and we point that
* at the efi_log_format structure embedded in the efi item.
* It is at this point that we assert that all of the extent
* slots in the efi item have been filled.
*/
STATIC void
xfs_efi_item_format(
struct xfs_log_item *lip,
struct xfs_log_iovec *log_vector)
{
struct xfs_efi_log_item *efip = EFI_ITEM(lip);
uint size;
ASSERT(atomic_read(&efip->efi_next_extent) ==
efip->efi_format.efi_nextents);
efip->efi_format.efi_type = XFS_LI_EFI;
size = sizeof(xfs_efi_log_format_t);
size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
efip->efi_format.efi_size = 1;
log_vector->i_addr = &efip->efi_format;
log_vector->i_len = size;
log_vector->i_type = XLOG_REG_TYPE_EFI_FORMAT;
ASSERT(size >= sizeof(xfs_efi_log_format_t));
}
/*
* Pinning has no meaning for an efi item, so just return.
*/
STATIC void
xfs_efi_item_pin(
struct xfs_log_item *lip)
{
}
/*
* While EFIs cannot really be pinned, the unpin operation is the last place at
* which the EFI is manipulated during a transaction. If we are being asked to
* remove the EFI it's because the transaction has been cancelled and by
* definition that means the EFI cannot be in the AIL so remove it from the
* transaction and free it. Otherwise coordinate with xfs_efi_release() (via
* XFS_EFI_COMMITTED) to determine who gets to free the EFI.
*/
STATIC void
xfs_efi_item_unpin(
struct xfs_log_item *lip,
int remove)
{
struct xfs_efi_log_item *efip = EFI_ITEM(lip);
if (remove) {
ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
if (lip->li_desc)
xfs_trans_del_item(lip);
xfs_efi_item_free(efip);
return;
}
__xfs_efi_release(efip);
}
/*
* Efi items have no locking or pushing. However, since EFIs are
* pulled from the AIL when their corresponding EFDs are committed
* to disk, their situation is very similar to being pinned. Return
* XFS_ITEM_PINNED so that the caller will eventually flush the log.
* This should help in getting the EFI out of the AIL.
*/
STATIC uint
xfs_efi_item_trylock(
struct xfs_log_item *lip)
{
return XFS_ITEM_PINNED;
}
/*
* Efi items have no locking, so just return.
*/
STATIC void
xfs_efi_item_unlock(
struct xfs_log_item *lip)
{
if (lip->li_flags & XFS_LI_ABORTED)
xfs_efi_item_free(EFI_ITEM(lip));
}
/*
* The EFI is logged only once and cannot be moved in the log, so simply return
* the lsn at which it's been logged. For bulk transaction committed
* processing, the EFI may be processed but not yet unpinned prior to the EFD
* being processed. Set the XFS_EFI_COMMITTED flag so this case can be detected
* when processing the EFD.
*/
STATIC xfs_lsn_t
xfs_efi_item_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
struct xfs_efi_log_item *efip = EFI_ITEM(lip);
set_bit(XFS_EFI_COMMITTED, &efip->efi_flags);
return lsn;
}
/*
* There isn't much you can do to push on an efi item. It is simply
* stuck waiting for all of its corresponding efd items to be
* committed to disk.
*/
STATIC void
xfs_efi_item_push(
struct xfs_log_item *lip)
{
}
/*
* The EFI dependency tracking op doesn't do squat. It can't because
* it doesn't know where the free extent is coming from. The dependency
* tracking has to be handled by the "enclosing" metadata object. For
* example, for inodes, the inode is locked throughout the extent freeing
* so the dependency should be recorded there.
*/
STATIC void
xfs_efi_item_committing(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
}
/*
* This is the ops vector shared by all efi log items.
*/
static const struct xfs_item_ops xfs_efi_item_ops = {
.iop_size = xfs_efi_item_size,
.iop_format = xfs_efi_item_format,
.iop_pin = xfs_efi_item_pin,
.iop_unpin = xfs_efi_item_unpin,
.iop_trylock = xfs_efi_item_trylock,
.iop_unlock = xfs_efi_item_unlock,
.iop_committed = xfs_efi_item_committed,
.iop_push = xfs_efi_item_push,
.iop_committing = xfs_efi_item_committing
};
/*
* Allocate and initialize an efi item with the given number of extents.
*/
struct xfs_efi_log_item *
xfs_efi_init(
struct xfs_mount *mp,
uint nextents)
{
struct xfs_efi_log_item *efip;
uint size;
ASSERT(nextents > 0);
if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
size = (uint)(sizeof(xfs_efi_log_item_t) +
((nextents - 1) * sizeof(xfs_extent_t)));
efip = kmem_zalloc(size, KM_SLEEP);
} else {
efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
}
xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
efip->efi_format.efi_nextents = nextents;
efip->efi_format.efi_id = (__psint_t)(void*)efip;
atomic_set(&efip->efi_next_extent, 0);
return efip;
}
/*
* Copy an EFI format buffer from the given buf, and into the destination
* EFI format structure.
* The given buffer can be in 32 bit or 64 bit form (which has different padding),
* one of which will be the native format for this kernel.
* It will handle the conversion of formats if necessary.
*/
int
xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
{
xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
uint i;
uint len = sizeof(xfs_efi_log_format_t) +
(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
uint len32 = sizeof(xfs_efi_log_format_32_t) +
(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
uint len64 = sizeof(xfs_efi_log_format_64_t) +
(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
if (buf->i_len == len) {
memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
return 0;
} else if (buf->i_len == len32) {
xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
dst_efi_fmt->efi_type = src_efi_fmt_32->efi_type;
dst_efi_fmt->efi_size = src_efi_fmt_32->efi_size;
dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
dst_efi_fmt->efi_id = src_efi_fmt_32->efi_id;
for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
dst_efi_fmt->efi_extents[i].ext_start =
src_efi_fmt_32->efi_extents[i].ext_start;
dst_efi_fmt->efi_extents[i].ext_len =
src_efi_fmt_32->efi_extents[i].ext_len;
}
return 0;
} else if (buf->i_len == len64) {
xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
dst_efi_fmt->efi_type = src_efi_fmt_64->efi_type;
dst_efi_fmt->efi_size = src_efi_fmt_64->efi_size;
dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
dst_efi_fmt->efi_id = src_efi_fmt_64->efi_id;
for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
dst_efi_fmt->efi_extents[i].ext_start =
src_efi_fmt_64->efi_extents[i].ext_start;
dst_efi_fmt->efi_extents[i].ext_len =
src_efi_fmt_64->efi_extents[i].ext_len;
}
return 0;
}
return EFSCORRUPTED;
}
/*
* This is called by the efd item code below to release references to the given
* efi item. Each efd calls this with the number of extents that it has
* logged, and when the sum of these reaches the total number of extents logged
* by this efi item we can free the efi item.
*/
void
xfs_efi_release(xfs_efi_log_item_t *efip,
uint nextents)
{
ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
if (atomic_sub_and_test(nextents, &efip->efi_next_extent))
__xfs_efi_release(efip);
}
static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_efd_log_item, efd_item);
}
STATIC void
xfs_efd_item_free(struct xfs_efd_log_item *efdp)
{
if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
kmem_free(efdp);
else
kmem_zone_free(xfs_efd_zone, efdp);
}
/*
* This returns the number of iovecs needed to log the given efd item.
* We only need 1 iovec for an efd item. It just logs the efd_log_format
* structure.
*/
STATIC uint
xfs_efd_item_size(
struct xfs_log_item *lip)
{
return 1;
}
/*
* This is called to fill in the vector of log iovecs for the
* given efd log item. We use only 1 iovec, and we point that
* at the efd_log_format structure embedded in the efd item.
* It is at this point that we assert that all of the extent
* slots in the efd item have been filled.
*/
STATIC void
xfs_efd_item_format(
struct xfs_log_item *lip,
struct xfs_log_iovec *log_vector)
{
struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
uint size;
ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
efdp->efd_format.efd_type = XFS_LI_EFD;
size = sizeof(xfs_efd_log_format_t);
size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
efdp->efd_format.efd_size = 1;
log_vector->i_addr = &efdp->efd_format;
log_vector->i_len = size;
log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
ASSERT(size >= sizeof(xfs_efd_log_format_t));
}
/*
* Pinning has no meaning for an efd item, so just return.
*/
STATIC void
xfs_efd_item_pin(
struct xfs_log_item *lip)
{
}
/*
* Since pinning has no meaning for an efd item, unpinning does
* not either.
*/
STATIC void
xfs_efd_item_unpin(
struct xfs_log_item *lip,
int remove)
{
}
/*
* Efd items have no locking, so just return success.
*/
STATIC uint
xfs_efd_item_trylock(
struct xfs_log_item *lip)
{
return XFS_ITEM_LOCKED;
}
/*
* Efd items have no locking or pushing, so return failure
* so that the caller doesn't bother with us.
*/
STATIC void
xfs_efd_item_unlock(
struct xfs_log_item *lip)
{
if (lip->li_flags & XFS_LI_ABORTED)
xfs_efd_item_free(EFD_ITEM(lip));
}
/*
* When the efd item is committed to disk, all we need to do
* is delete our reference to our partner efi item and then
* free ourselves. Since we're freeing ourselves we must
* return -1 to keep the transaction code from further referencing
* this item.
*/
STATIC xfs_lsn_t
xfs_efd_item_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
/*
* If we got a log I/O error, it's always the case that the LR with the
* EFI got unpinned and freed before the EFD got aborted.
*/
if (!(lip->li_flags & XFS_LI_ABORTED))
xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
xfs_efd_item_free(efdp);
return (xfs_lsn_t)-1;
}
/*
* There isn't much you can do to push on an efd item. It is simply
* stuck waiting for the log to be flushed to disk.
*/
STATIC void
xfs_efd_item_push(
struct xfs_log_item *lip)
{
}
/*
* The EFD dependency tracking op doesn't do squat. It can't because
* it doesn't know where the free extent is coming from. The dependency
* tracking has to be handled by the "enclosing" metadata object. For
* example, for inodes, the inode is locked throughout the extent freeing
* so the dependency should be recorded there.
*/
STATIC void
xfs_efd_item_committing(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
}
/*
* This is the ops vector shared by all efd log items.
*/
static const struct xfs_item_ops xfs_efd_item_ops = {
.iop_size = xfs_efd_item_size,
.iop_format = xfs_efd_item_format,
.iop_pin = xfs_efd_item_pin,
.iop_unpin = xfs_efd_item_unpin,
.iop_trylock = xfs_efd_item_trylock,
.iop_unlock = xfs_efd_item_unlock,
.iop_committed = xfs_efd_item_committed,
.iop_push = xfs_efd_item_push,
.iop_committing = xfs_efd_item_committing
};
/*
* Allocate and initialize an efd item with the given number of extents.
*/
struct xfs_efd_log_item *
xfs_efd_init(
struct xfs_mount *mp,
struct xfs_efi_log_item *efip,
uint nextents)
{
struct xfs_efd_log_item *efdp;
uint size;
ASSERT(nextents > 0);
if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
size = (uint)(sizeof(xfs_efd_log_item_t) +
((nextents - 1) * sizeof(xfs_extent_t)));
efdp = kmem_zalloc(size, KM_SLEEP);
} else {
efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
}
xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
efdp->efd_efip = efip;
efdp->efd_format.efd_nextents = nextents;
efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
return efdp;
}